If the map is large or huge and you have fewer than the default number of civ, they will have less reason to fight. They will just keep expanding as long as there is room.
Once room to grow is low or gone, then they have to fight, the whom is the question. Mostly they go for the civ that is weaker, if that is you, then tag your it.
Remember they will often bribe others to join, so will will soon have few friends.
If you are strong and get large, they will probably hate you eventually and go to war with you. This, even if, you are too strong for them. Well, up to a point.
Even at Sid I have had a civ or two leave me alone, if I was very strong and had been dealing with them.
I would also point out that you may not want them to war at level above DG, as one of them may get too much out of the war and be more dangerous.
You have to be careful not to get a civ dogpiled, when the AI gains more than you will.